20871717552 has 160 divisors (see below), whose sum is σ = 68691317760. Its totient is φ = 5943905280.

The previous prime is 20871717539. The next prime is 20871717577. The reversal of 20871717552 is 25571717802.

20871717552 is a `hidden beast` number, since 2 + 0 + 87 + 1 + 7 + 17 + 552 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 20871717498 and 20871717507.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 929368 + ... + 951560.

It is an arithmetic number, because the mean of its divisors is an integer number (429320736).

Almost surely, 2^20871717552 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20871717552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34345658880).

20871717552 is an abundant number, since it is smaller than the sum of its proper divisors (47819600208).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20871717552 is a wasteful number, since it uses less digits than its factorization.

20871717552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22528 (or 22516 counting only the distinct ones).

The product of its (nonzero) digits is 274400, while the sum is 45.

The spelling of 20871717552 in words is "twenty billion, eight hundred seventy-one million, seven hundred seventeen thousand, five hundred fifty-two".